1. Field of the Invention
This invention relates to new and improved switchboard apparatus, and, in particular, to switchboard housing apparatus. Accordingly, it is a general object of this invention to provide new and improved apparatus of such character.
2. Description of the Prior Art
In the past, a cubicle of iron or steel was built that was rigid and free-standing. Switchgear equipment would be bolted or welded to the sides of the cubicle for support. In some prior art switchboards, the bulk of unit, including operational portions, is supported by the sides of a frame. Both the left and right hand sides of the frame act as covers and as support members for the switchgear.
In the past, insulative supports were used to support a plurality of bus bars.
In the past, it was common to have bus bars of the same phase sandwiched together in close proximity to each other, but spaced apart. Disadvantageously however, three such bars would not carry thrice as much current as one bar because, at high amperage ratings, such as 1000 or 2000 amperes at 60 cycles, due to the skin effect, electrons would tend to flow along the outer surface. Thus, with three bars in parallel, the current would tend to be carried primarily by the outer two bars and not by the inner bar. Distribution bus bars of the prior art usually suffered from one or more disadvantages. Prior art bus bars may have had a disadvantage of lacking the ability to greatly dissipate heat, or lacking the accommodation of permitting a bolt to slide along a grooveway therein. In the event of short circuits, prior bus bars may have had the tendency to bend or whip around in an uncontrolled manner upon the passage of high amounts of current.